scholarly journals OPTICAL SPECTRA AND REACTIVITY OF ORGANIC FREE RADICALS FORMED BY REACTION OF HYDROXYL FREE RADICAL WITH PYRIMIDINE BASES: A PULSE RADIOLYSIS STUDY.

1969 ◽  
Author(s):  
L Myers, Jr ◽  
M Hollis ◽  
L Theard ◽  
F Peterson
Keyword(s):  
Free Radicals ◽  
Free Radical ◽  
Pulse Radiolysis ◽  
Optical Spectra ◽  
Hydroxyl Free Radical ◽  
Pyrimidine Bases

Research on the Antioxidation of Polyrhachis vicina Wine

2013 ◽  
Vol 781-784 ◽  
pp. 1689-1693
Author(s):  
Jing Xian Sun ◽  
Hai Ying Yang ◽  
Ping Zhou ◽  
Guang Qiu Zhang ◽  
Gang Du ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Free Radicals ◽  
Free Radical ◽  
Fenton Reaction ◽  
Superoxide Radical ◽  
Scavenging Effect ◽  
Hydroxyl Free Radical ◽  
Dpph Scavenging ◽  
Polyrhachis Vicina ◽  
Pyrogallol Autoxidation

The antioxidant activity of Polyrhachis vicina wine extract was investigated: The IC50 of scavenging effect on superoxide radical generated by Pyrogallol autoxidation was 0.37 mg/mL; the maximum scavenging rate was 81.4%. The IC50 of scavenging effect on hydroxyl free radical generated by Fenton reaction was 0.66 mg/mL; the maximum scavenging rate was 91.8%. The IC50 of DPPH· scavenging effect was 0.48 mg/mL; the maximum scavenging rate was 91.4%. The results indicated that Polyrhachis vicina wine extract showed activity both in scavenging free radicals and antioxidation.

scholarly journals Antioxidants into Nopal (Opuntia ficus-indica), Important Inhibitors of Free Radicals’ Formation

Antioxidants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2006
Author(s):  
Romina Castañeda-Arriaga ◽  
Adriana Perez-Gonzalez ◽  
Tiziana Marino ◽  
Nino Russo ◽  
Annia Galano
Keyword(s):  
Free Radicals ◽  
Free Radical ◽  
Density Functional ◽  
Copper Ions ◽  
Free Energies ◽  
Opuntia Ficus Indica ◽  
Hydroxyl Free Radical ◽  
Diffusion Limited ◽  
Biological Interest ◽  
Nutritional Benefits

Nopal (Opuntia ficus indica) belonging to the Cactacea family has many nutritional benefits attributed to a wide variety of phenolic and flavonoid compounds. Coumaric acid (COA), ferulic acid (FLA), protocatechuic acid (PRA), and gallic acid (GAA) are the phenolic acids (PhAs) present in nopal. In this study, the role of these PhAs in copper-induced oxidative stress was investigated using the density functional theory (DFT). The PhAs form 5 thermodynamically favorable complexes with Cu(II), their conditional Gibbs free energies of reaction (ΔG’, at pH = 7.4, in kcal/mol) are from −23 kcal/mol to −18 kcal/mol. All of them are bi-dentate complexes. The complexes of PRA and GAA are capable of inhibiting the Cu(II) reduction by both O2•− and Asc−, their reactions with the chelated metal are endergonic having rate constants about ~10−5–102 M−1 s−1, PhAs can prevent the formation of hydroxyl free radicals by chelating the copper ions. Once the hydroxyl radicals are formed by Fenton reactions, the complexes of PhAs with Cu(II) can immediately react with them, thus inhibiting the damage that they can cause to molecules of biological interest. The reactions between PhAs-Cu(II) complexes and hydroxyl free radical were estimated to be diffusion-limited (~108 M−1s−1). Thus, these chelates can reduce the harmful effects caused by the most reactive free radical existent immediately after it is formed by Fenton reactions.

The reaction of copper(II) complexes of macrocyclic dioxotetraamines with hydroxyl free radical—A kinetic study by pulse radiolysis

1997 ◽  
Vol 49 (4) ◽  
pp. 465-468 ◽  
Author(s):  
Wang Jun ◽  
Luo Qin-Hui ◽  
Feng Chang-Jian ◽  
Shen Meng-Chang ◽  
Yao Si-De ◽  
...  
Keyword(s):  
Free Radical ◽  
Kinetic Study ◽  
Pulse Radiolysis ◽  
Hydroxyl Free Radical

Study of antioxidant potential in leaves, stems, nuts of Juglans regia L.

2012 ◽  
Vol 1 (10) ◽  
pp. 79 ◽  
Author(s):  
G. Raja* ◽  
Ivvala Anand Shaker ◽  
Inampudi Sailaja ◽  
R. Swaminathan ◽  
S. Saleem Basha ◽  
...  
Keyword(s):  
Free Radicals ◽  
Free Radical ◽  
Antioxidant Activities ◽  
Radical Scavenging Activity ◽  
Juglans Regia ◽  
Radical Scavenging ◽  
Antioxidant Compounds ◽  
Free Radical Damage ◽  
Radical Damage

Natural antioxidants can protect the human body from free radicals and retard the progress of many chronic diseases as well as lipid oxidative rancidity in foods. The role of antioxidants has protected effect against free radical damage that may cause many diseases including cancer. Primary sources of naturally occurring antioxidants are known as whole grains, fruits, and vegetables. Several studies suggest that regular consumption of nuts, mostly walnuts, may have beneficial effects against oxidative stress mediated diseases such as cardiovascular disease and cancer. The role of antioxidants has attracted much interest with respect to their protective effect against free radical damage that may cause many diseases including cancer. Juglans regia L. (walnut) contains antioxidant compounds, which are thought to contribute to their biological properties. Polyphenols, flavonoids and flavonols concentrations and antioxidant activity of Leaves, Stems and Nuts extract of Juglans regia L. as evaluated using DPPH, ABTS, Nitric acid, hydroxyl and superoxide radical scavenging activity, lipid peroxidation and total oxidation activity were determined. The antioxidant activities of Leaves, Stems and Nuts extract of Juglans regia L. were concentration dependent in different experimental models and it was observed that free radicals were scavenged by the test compounds in all the models.

THE KINETICS OF THE THERMAL REACTIONS OF ETHYLENE OXIDE

1963 ◽  
Vol 41 (12) ◽  
pp. 2956-2961 ◽  
Author(s):  
M. Lynne Neufeld ◽  
Arthur T. Blades
Keyword(s):  
Free Radicals ◽  
Free Radical ◽  
Ethylene Oxide ◽  
Thermal Reactions ◽  
Kinetics Of

The thermal reactions of ethylene oxide in the presence of an excess of propylene have been studied as a function of pressure and it has been found that there are two sets of products, acetaldehyde and free radicals, presumably methyl and formyl. These products are believed to arise from an excited acetaldehyde intermediate. Some evidence has been obtained for the occurrence of a surface-catalyzed rearrangement to acetaldehyde but the free radical products are uninfluenced by surface.

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